<template>
  <div class="app">
    <h3>我是App组件（祖）{{name}}--{{price}}</h3>
    <Child/> 
  </div>
</template>

<script>
import { reactive,toRefs } from '@vue/reactivity'
import Child from './components/Child.vue'
import { provide } from '@vue/runtime-core'

  export default {
    name:'App',
    components:{Child},
    setup(){
      let car = reactive({
        name:'奔驰',
        price:'40W'
      })
      provide ('car',car)  //给自己的后代组件传递数据
      return {
        ...toRefs(car)
      }
    }
  }
</script>

<style>
  .app {
    background-color: gray;
    padding: 10px;
}

</style>